1 . High-resolution (高分辨率) satellite imagery has been used to map every single tree in Africa, showing a technique that could help improve the monitoring of deforestation (森林砍伐) across the world. Florian Reiner at the University of Copenhagen, Denmark, and his colleagues used images from sate lies to map canopy (树冠) across the entire African continent.

Modern sate lies usually catch tree canopies at a resolution of 30 meters — fine for measuring the size of forests, but less good at mapping individual trees. The satellite data Reiner and his colleagues used had a resolution of 3 meters, enabling the study to map all trees, including those not part of a forest.

The results suggest that 30 percent of all trees in Africa aren’t in a forest and instead are across farmland, savannah and urban areas. “Many countries in Africa lack thick forests, but have a lot of trees.” says Reiner. “These trees are extremely important to the local ecosystems, the people and the economy. By tracking every single tree, researchers can start to monitor how these trees are coping with climate change or whether they are sensitive to deforestation.” It could also improve the monitoring of reforestation efforts, which are growing in popularity as a way of removing carbon dioxide from the atmosphere.

“At a local level, being able to consistently monitor when and where trees are disappearing or reappearing can lead to more actionable insights,” says John Francis at the Alan Turing Institute in London.

“The study is a proof of concept rather than a map ready for immediate commercial use,” says Reiner. “It’s research work. It’s showing what could be done,” he says. But he is already working with colleagues to scale up the tracking approach to cover the entire global canopy: “We’re hoping that this will be seen as a way forward in monitoring tree resources.”

1. Why is high-resolution satellite imagery used to map every single tree?

A．To know the exact height of the tree.

B．To have a clear picture of the canopy.

C．To help monitor the deforestation.

D．To improve the satellite technology.

2. What is John Francis’ attitude towards the map?

A．Doubtful.

B．Disapproving.

C．Indifferent.

D．Favorable.

3. What do Reiner and his colleagues expect to do?

A．Protect the trees only in Africa.

B．Put the map into commercial use.

C．Track the entire global canopy.

D．Improve the imagery technology.

4. What is probably the best title?

A．Ways to Measure the Size of Forests in Africa

B．Coping with Climate Change by Tracking Every Single Tree

C．A Map from the Satellite Ready for Immediate Commercial Use

D．High-resolution Satellite Imagery Used in Monitoring Deforestation

2 . Thirsty or stressed plants do not suffer in silence. Instead, they make high-pitched(尖锐的) sounds, according to a study published in the journal Cell.

The reason why you have probably never heard the plants’ sounds is that most humans are only able to hear sounds as high as 20 kilohertz (kHz), but the plants made sounds mostly between 40 and 80 kHz, Lilach Hadany, a co-author of the study at Tel Aviv University, tells Business Insider’s Marianne Guenot.

Plants, obviously, do not have organs to make sounds. Lilach says, the present popular theory on how they make noises centers on plants’ xylem(木质部), the tubes that transport water from their roots to their stems(根茎) and leaves. In the process of transporting, when an air bubble(气泡) forms or breaks in the xylem, it might make a little noise; bubbles are more likely to form when a plant is suffering from drought. But the exact process requires further study, Lilach explains.

To listen in to plants, Lilach and her co-workers placed tobacco and tomato plants in small boxes equipped with microphones. First, they stopped providing water to some plants in the boxes and cut the stems of others. Then, the microphones were used to pick up any noises made by the plants even though they couldn’t hear them. Researchers found that the sounds did show the specific types of stresses plants were experiencing. Thirsty tomato and tobacco plants made an average of about 35 and 11 sounds per hour, individually, while cut tomato and tobacco plants made 25 and 15 noises per hour.

In theory, these recorded sounds could help farmers know about which crops are most in need of water. “When more and more areas are exposed to drought due to climate change, efficient water use becomes even more important, for both food security and ecology,” Lilach with her co-workers write.

1. Why do humans fail to hear the sounds of plants?

A．The sounds are stressful.

B．The sounds are beyond human’s hearing range.

C．The sounds are low-pitched.

D．The sounds are between 20kHz and 40kHz.

2. What might cause thirsty plants to produce sounds?

A．Suffering from lack of air.

B．Stems and leaves transporting water.

C．More air bubbles gathering in the roots.

D．Air bubbles’ forming or breaking in the xylem.

3. What did Lilach and her co-workers find in the study?

A．Noises can be picked up by microphones.	B．Plants make more sounds in small boxes.
C．Cut plants suffer the same as thirsty ones.	D．Different sounds indicate plants’ stress types.

4. What’s the potential use of the sound recordings?

A．To harvest the crops.	B．To solve the food problem.
C．To locate the thirsty crops.	D．To prevent climate change.

3 . 听下面一段较长对话,回答以下小题。
1. What are the speakers discussing?

A．The man’s house.

B．The effects of global warming.

C．The man’s job.

2. What is always nice according to the man?

A．Animals can get more food.

B．Green can be seen all year round.

C．He lives by the sea.

3. What could farmers grow before?

A．Grass.

B．Vegetables.

C．Trees.

4 . Research has revealed many benefits to being in the presence of nature, whether that’s walking in a forest, having a small garden or keeping a few household plants.

“One study showed that patients in a hospital who had plants in their rooms reported less pain, lower blood pressure, less tiredness and less anxiety than patients without plants in their rooms,” says Jenny Seham, founder and director of AIM (Arts and Integrative Medicine) in New York. She explains,“Cortisol (皮质醇)，the stress hormone, has been shown to lower with plant interaction, lowering tiredness and blood pressure. Gardening and caring for plants can help turn people away from negative thoughts or emotions.”

Houseplant collections have become a popular social media trend. Jamie Keaton Jones, a psychologist, says, “For many people, tending to plants has become a hobby. This hobby enables them to experience greater comfort and beauty from the presence of living things sharing their space.”

“Plants and exposure to greenery have been found to have many mental health benefits, such as lowering stress, decreasing feelings of depression, increasing sociability, restoring focus, improving cognitive performance, improving mood and increasing self- confidence,” says Jones.

Studies have also shown that plants and gardening increase productivity and levels of serotonin (血清素), which is responsible for uplifting mood.

“Rather than focusing on the past or worrying about the future, plant care helps one concentrate on the present moment and provides a feeling of accomplishment,” says Gayle Weill, another psychologist in Washington.

Like any new skill or hobby, taking care of houseplants comes with a learning process. Anyone starting to care for plants should be patient and allow themselves time to learn the basics, leaving room for a little trial and error.

1. Where can the passage be found?

A．In a science magazine.	B．In a novel.
C．In a history book.	D．Ina biography.

2. What can we infer from Jenny Seham’s words?

A．Many hospitals keep plants in the patients’ rooms.

B．Doctors will use plants to cure the patients’ illness.

C．Keeping a few plants can get u out of tiredness.

D．Caring for plants can keep us away from bad mood.

3. What can we learn from the passage?

A．Houseplant collections are not popular in recent days.

B．Keeping plants has many physical health benefits.

C．Studies have proved that plants are beneficial for uplifting mood.

D．For many of us, plant care is difficult and takes time.

4. Which of the following is a suitable title for the passage?

A．Benefits of Keeping Houseplants	B．Research on Keeping Houseplants
C．Ways to Take Care of Houseplants	D．Opinions About Caring About Plants

5 . Increased human activity and climate change have caused a rise of algae (藻类植物) in water bodies around the world—sometimes choking ecosystems of sunlight and oxygen. In more extreme cases, they can produce dangerous poisons that can sicken or kill people and animals. But the plenty of algae could prove crucial as our population rises beyond eight billion people worldwide because algae are crops that don’t need land, freshwater, or fertilizer to fill nutritional gaps.

And even though they are so closely associated with human’s bad impact on Earth, algae could also play vital roles in slowing climate change and helping fight against pollution, viruses, and more. With microplastic pollution documented in almost all habitats related to water, a study showed that algae can help filter microplastics from water. Algae can also filter chemicals that can be used for fertilizer.

Algae can produce more effective biofuel than traditional sources. Rescarchers at a German algae growing facility are already using it to fuel plane. Researchers believe this and other sustainable fuels could reduce carbon released from airplanes by up to 80 percent.

Animal feed containing a kind of red algae reduces harmful methane(甲烷)released from cattle by more than 80 percent. The addition works by changing the environment in a cow’s stomach, stopping the production of methane before it can be released.

Red algae can stop the copies of some viruses, and have been shown to stimulate the body’s immune (免疫的) system and could become a powerful anti-HIV medicine.

In 2019, freshwater algae were launched into space to change the CO² breathed out by astronauts on the International Space Station into oxygen. Since algae are also high in protein, they could replace up to 30 percent of astronaut food in the future.

1. What can we know about algae from the first paragraph?

A．Better late than never.	B．Every coin has two sides.
C．All is well that ends well.	D．Two heads are better than one.

2. Why do algae have a positive impact on environment ?

A．They avoid climate change.	B．They absorb pollutants in the air.
C．They reduce microplastics in the water.	D．They filter most poisonous chemicals.

3. What can algae help in our life?

A．Change animal feed into methane.

B．Store carbon released from airplanes.

C．Help researchers to create traditional sources.

D．Create biofuel and reduce methane in cows’s stomach.

4. How do algae benefit human’s health?

A．By helping fight against diseases.	B．By increasing human’s strength.
C．By producing more oxygen than other plants.	D．By replacing much food for astronauts.

6 . Forests are feeling the heat. In places like the American West, rising temperatures and drought mean less water for trees. Now, scientists have found that thinning early in forest growth creates tougher trees that can endure climate change. What’s more, these thinned forests can suck carbon out of the air just as fast as thick forests.

“When it comes to carbon storage and climate change adaptation, we can have our cake and eat it too,” says Andrew Larson, forest ecologist and author of the new study. “It’s a win-win.”

As trees grow, they convert carbon dioxide to food and store it in their leaves, trunks, and roots. But if trees get too crowded, they compete for light and water. Removing some trees can ease the competition, letting the remaining trees grow big and healthy. But scientists worry that removing trees can reduce forest carbon storage.

To see whether the climate trade-off truly exists, scientists tapped into a long-term experiment in northwestern Montana. In 1961, U.S. Forest Service officials started the experiment in a young forest of western larch. The forest was broken up into plots. In some plots, the 8-year-old trees were thinned from tens of thousands per hectare down to 494 per hectare. These trees grew thick trunks and broad tree shades. Other plots were left alone, and the trees there grew tall and skinny as they competed for sunlight. The original study was rooted in an interest in growing timber rapidly. But the scientists at the University of Montana sprouted a new question: How did tree density (密度) influence carbon storage?

To find out, they measured tree height, diameter, and width of branches to estimate the amount of carbon stored. They also calculated the carbon contained in other plants, dead wood, and forest floor debris. The research showed total carbon was nearly the same in both forests. The un-thinned forest had more trees, but the thinned forest compensated with bigger trees.

1. What is scientists’ finding about forests?

A．The tougher trees in thinned forests stand climate change.

B．Thinned forests have as much carbon as thick forests.

C．The American forests are suffering sever heat wave.

D．The thick forests grow rapidly than thinned ones.

2. What does the underlined part in Paragraph 2 imply?

A．We are able to produce and enjoy a cake together.

B．Carbon storage and climate stability are the final goals.

C．We can choose between carbon storage and climate change.

D．Carbon storage and climate adaptation can be achieved meanwhile.

3. How did the US Forest Service officials conduct their study?

A．Through observing forests grow.

B．Through comparative experiments.

C．By providing examples to illustrate.

D．By collecting massive amounts of data.

4. What’s the purpose of the research mentioned in paragraph 5?

A．To achieve how to plant trees scientifically.

B．To test how much carbon forests contain.

C．To prove the advantages of thinned forests.

D．To see how tree density affects carbon storage.

7 . This summer, nearly 65 percent of the United States is experiencing “unusually dry” weather. More than 109 million people are living under drogue conditions.     1     So how to garden when there’s a lack of water?

    2    Newly planted trees and shrubs(灌木)should be put on the top of the watering list. They require regular watering until their roots get deep into the soil. That process can take a full year. Vegetables such as beans, cabbage, and lettuce also have high water needs. None will likely survive with little water.

Most plants require an average of 2 to 4 centimeters of water each week under normal conditions. That need could increase, however, during periods of extreme heat, when the soil dries out more quickly.     3     Divide it over two or three times per week.

Use deeper, less-frequent watering instead of daily sprinkles(洒水)which can be wasteful? Watering deeply also leads to stronger, deeper roots that are better able to support plants when there’s no surface water. So avoid using overhead sprinklers.     4     You can place watering devices on the soil directly over roots.

Consider using recycled household water, also called gray water, to water plants. Unsalted water left over from boiling eggs or vegetables provides extra nutrients(营养物). Dish and bath water that is not too soapy will not harm plants. And water captured(捕获)while cleaning fruits and vegetables can be used around the garden.     5    .

A．So learn how to water plants correctly.

B．So make good use of water in your house.

C．You should water newly planted trees regularly.

D．A lot of them have plants or yards to worry about.

E．First you should decide which plants need water the most.

F．Do not offer your plants their weekly water needs all at once.

G．They wet the leaves and other areas instead of directing water to plant roots.

8 . How to create an indoor garden

If you’re looking for a way to brighten up your home, consider creating an indoor garden.     1     We will share some basic tips on how to make yours look its best.

Know the type of plants you want

Deciding is probably the hardest part when it comes to creating an indoor garden because there are just so many plants to choose from. Start by thinking about what type of plants you want.

    2     Or maybe something that doesn’t need much attention or effort? Once you have an idea of the type of plant you want, you can start narrowing down your options.

Get the right potting soil and containers

Now that you know what type of plants you want, it’s time to get the right potting soil and containers. Make sure to get a potting mix that is specifically designed for indoor plants.     3     As for containers, you can really use anything as long as it has drainage holes.

Choose a bright location Once you have your plants and pots, it’s time to choose a location for your indoor garden.     4     This will help your plants grow and stay healthy. If you don’t have a spot that gets a lot of light, you can always use artificial lighting like grow lights.

    5    

In addition to watering, you’ll also need to add substance to your plants about once a month. This will help them grow and stay healthy. Just be sure to follow the instructions on the package. Don’t overdo it.

A．Give fertiliser monthly.

B．How exactly can we make one?

C．Follow the instruction correctly.

D．But don’t worry, we’re here to help.

E．This will help your plants grow strong.

F．Do you want something that will blossom?

G．Look for a spot in your home that gets a lot of natural light.

9 . Many fruit trees and bushes are very simple to plant using no equipment except some potting soil and a heating equipment. In fact, you can get a handful of cuttings for free from a friend during pruning (修剪) season and end up with a whole homemade fruit farm.

Grapes

They are the first easy species on my list because they will grow in most parts of the US and are easy to root from hardwood cuttings. Hardwood cuttings are pieces of one-year-old wood taken in the late winter before the buds start to grow.

Figs

They are just easy to root, but I put them second on my list because northerners will have a hard time keeping the plants alive. If you live party way north, you can grow figs as long as you choose a cold-hardy variety.

Rabbiteye blueberries

They are an example of another kind of self-rooting plant. After a few years, it will begin to send up suckers from near the base. The suckers that are at least a few inches away from the parent plant will generally grow roots a year after emerging, at which point you can dig down until you’ve found several roots.

Gooseberries

They are simple because they just about root themselves. If you allow (or force) one branch to grow along the ground, then cover part of the branch with rich soil, roots will grow on the underwater part. Cut their stems off next year and you’ll have one or more gooseberry plants to set out elsewhere.

1. What makes grapes the first easy species on the author’s list?

A．Their high production.	B．Their delicious and special taste.
C．Their great economic value.	D．Their strong adaptability to grow.

2. When will you get new gooseberry plants?

A．After growing along the ground.

B．Before covering part of the branch.

C．After cutting their stems the next year.

D．Before roots grow on the underwater part.

3. In which section of a newspaper may this text appear?

A．Science.

B．Gardening.

C．Fashion.

D．Entertainment.

10 . It could be said that trees naturally call for attention as they climb toward the sky with their arms outstretched. Yet, it’s still easy for us to ignore them. As we rush through our own day-to-day lives, trees seem to play the role of an insignificant backdrop.

Nothing could be further from the truth. Rooted to a single spot, trees appear sill.But that stillness is not associated with laziness. In fact, trees are guards of the planet as the impact of their hard work carries miles farther than the ground in which they stand.

Globally, trees are the most cost-effective tool in promoting biodiversity. They support the survival of a significant number of animals. For example, a big reason why ring-tailed lemurs (狐猴) are endangered is that half of the forests they depend on in Madagascar off the East coast of Africa were cut down.

Not only do animals depend on trees for shelter, trees are significant to the health of humans as well. In fact, doctors in Canada are so convinced of trees’ benefits for the mind and body that they recommend patients visit national parks. Trees help a lot in tackling climate change too. They absorb and store carbon dioxide(CO2) — the key greenhouse gas emitted by our cars and power plants — before it has a chance to reach the upper atmosphere and trap heat around the Earth’s surface.

So it’s time to put trees in the spotlight. The Arbor Day Foundation, the world’s largest nonprofit, is devoted to this exact mission: inspiring people to plant,protect, and honor trees. We know there’s never been a more important time for trees. And we know there’s never been a more important time for mankind to engage in its role as environmental guards. This isn’t a one-sided relationship. What we give to nature we will receive in return, tenfold (十倍地). So as springtime arrives once again, take a moment and appreciate what a tree can be.

1. What does the author mainly want to tell us by giving the example of ring-tailed lemurs?

A．Trees are insignificant for their stillness.

B．Trees play a vital role in cleaning the air.

C．Trees provide critical habitats for creatures.

D．Half of the forests in Madagascar were cut down.

2. What does the author intend to do in the last paragraph?

A．To provide advice on planting trees.

B．To call for human attention to trees.

C．To show the best time of planting trees.

D．To stress the impact of trees on humans.

3. Which of the following best shows the structure of the text?
1=Paragraph One 2= Paragraph Two 3= Paragraph Three 4= Paragraph Four 5=Paragraph Five

A．

B．

C．

D．

4. What can be a suitable title for the text?

A．Trees: Cleaners of the Environment	B．Trees: Shelters for Creatures
C．Trees: Defenders of Human Health	D．Trees: Guards of the Planet